This invention relates to spa jets for hydrotherapy. In particular, it relates to a spa jet having a rotating nozzle supported by a radial ball bearing in which clogging of the bearing by debris in the spa water is reduced.
In the art of hydrotherapy, it is known to utilize spa jets which direct a stream of water into the spa through one or more nozzles which rotate to distribute the water in a swirling motion against the skin of a person in the spa. Such a spa jet typically includes a housing, which communicates with an inlet connected to a pressurized source of water, and a radial ball bearing, mounted within the open end of a cup-shaped portion of the housing, which supports the nozzle for rotation. The nozzle has a nozzle passage which is angularly and radially offset from the central axis of the spa jet so that the water jet exerts a turning moment to the nozzle to rotate it. One such spa jet of the type described is disclosed in U.S. Pat. No. 6,123,274 to Perdreau et al., owned by the assignee of the present invention.
While spa jets of the type described are generally satisfactory for their intended purpose, debris within the spa water can, over time, impair the free rotation of the radial ball bearing supporting the nozzle. Build-up of debris in the bearing can eventually slow down rotation of the nozzle to an unacceptable rate and, in an ultimate condition, cause it to stop rotating. This impairment can have several causes. For example, there will usually be gummy substances within the spa water, such as body oils or suntan oil, which build up over time on ball bearings, and on other rotary surfaces, within the rotary bearing. In addition, there will usually be fine particulates, such as sand or insoluble earth particles and undissolved particulate residues from the chlorine-containing tablets used in the spa to kill bacterial organisms. There may also be human hair and also particles of plastic. These particles can enter and wedge against, or roughen, the surfaces of rotating parts thereby causing them to slow down or cease to rotate. For purposes of this patent, we will use the term xe2x80x9cdebrisxe2x80x9d to refer collectively to all substances dissolved, suspended, entrained or otherwise present in the spa water, that tend to impair free rotation of the radial ball bearing. We will also use the word xe2x80x9ccloggingxe2x80x9d to generically describe any interference with rotation of the rotary bearing caused by the debris.
While rotary spa jets, of the type described, will operate for long periods before the rotation of the spa jet becomes impaired to the point of inutility, it is an objective of this invention to extend the life of the spa jet by minimizing the clogging of the rotary bearing.
The present invention provides an improvement to a spa jet of the type having an inlet tube, supplied by an upstream source of water under pressure, a cup-shaped housing extending and flaring outwardly from a downstream end of the inlet tube, a radial ball bearing having outer and inner races mounted within and surrounding the downstream end of the housing and a nozzle member mounted to the inner race, wherein there is a nozzle passage through the nozzle member which is offset relative to the central axis so that the water jet leaving the nozzle causes the nozzle to rotate. A minor part of the water flow is directed through the bearing to lubricate and flush it.
The improvement resides in structure which reduces and slows down flow of water internally within the spa jet reaching the radial ball bearing. The invention thereby diminishes the amount of debris within the water that passes through the bearing thereby prolonging the life of the bearing before it becomes unacceptedly slowed in its freedom to rotate.
In particular, the present invention provides a generally cup-shaped flow guide, mounted within the housing, which includes at least one baffle wall that reduces the amount of water and debris within it that reaches the bearing. The baffle wall extends towards the adjacent surfaces of the nozzle member to guide flow back toward the nozzle and thus reduce the flow reaching the bearing. In addition to reducing the amount of water flowing to the bearing, the baffle wall also reduces the turbulence to cause settlement of some of the debris before the water reaches the bearing. Any settled-out particulates can collect in a first debris pocket defined by the region between the flow tube and the baffle wall.
The flow guide also provides a second baffle wall which extends axially to a position spaced closely adjacent to the rotary bearing, with only a small gap through which water can flow to the bearing so that the flow of water reaching the rotary bearing is further reduced. Additional settlement of some of the debris will occur and it is collected in a second debris pocket between the two baffle walls.
The intended result of the improved structure described is to prolong the time for which the nozzle member can rotate before significant impairment is caused by debris reaching the radial ball bearing.